CHATTANOOGA (WRCB) -- The triple-digit heat gripping the Tennessee Valley can render your medications useless.

"All medications should be kept at or below 78 degrees," says Curt Coley, a pharmacist at a Chattanooga Walgreens. They always make sure of this at their stores.

This is why he says to never leave any medications sitting in your car too long, especially on days when the outside temperature is expected to be exceptionally warm or hot. The temperature inside your vehicle can be ten degrees or more hotter than the air temperature outside. 

"Don't go shopping for a couple of hours after you pick up your medications. Try to get them home," advised Coley.

This is because the fiery temperatures will break down and degrade the medicines, making it then virtually useless. It won't make them dangerous to take, but they will be less effective. Then you'll have to shell out more money for replacements.

"It's going to be a waste of their money and their therapy is not going to be controlled properly," explains Coley.

The same goes for medications ordered through the mail. They'll get cooked inside your mailbox if left there too long on a hot day.

If you don't have air conditioning, don't worry. Coley says most medications can be refrigerated once you get home.

"There are a few exceptions like some re-constituted oral liquid antibiotics," says Coley.

But even if you've kept your medications stored at the proper temperature from minute one, you may be in danger once you go outside after taking certain ones. Lithium, as well as some potassium supplements, can have adverse reactions to the blazing heat and become poisonous.

"The risk of dehydration. Raising the blood levels to toxic levels and things of that nature," says Coley.

So he suggests to always check with your pharmacist and drink plenty of water while taking these treatments, especially when mother nature cranks up the heat.

Coley also says while refrigerating most medications is okay, never put them in the freezer. This will degrade them as much as intense heat.

He goes on to say that these rules for proper storage apply to over-the-counter drugs as well as prescriptions.